Acartia jilletti is a species of marine copepod

Copepod

Copepods are a group of small crustaceans found in the sea and nearly every freshwater habitat. Some species are planktonic , some are benthic , and some continental species may live in limno-terrestrial habitats and other wet terrestrial places, such as swamps, under leaf fall in wet forests,...

 belonging to the family Acartiidae

Acartiidae

Acartiidae is a family of calanoid copepods distinguishable by the rostral margin not being extended. They are epipelagic, planktonic animals, not being found below a depth of . There are over 100 described species distributed throughout the world's oceans, mainly in temperate areas....

. This species has a total length of up to 1 mm. It is very similar to Acartia ensifera

Acartia ensifera

Acartia ensifera is a species of marine copepod belonging to the family Acartiidae. This is a slender copepod, around 0.8 - 0.9 mm in length, with distinctively long caudal rami. It is found around the coasts of New Zealand .-References:*...

but the female can be distinguished by the shorter caudal rami

Caudal ramus

The caudal ramus is a characteristic feature of primitive crustaceans. Located on the anal somite , the caudal ramus is a pair of appendage-like or spine-like protrusions. Specific structures which are rod or blade-like are referred to as caudal furca....

 and the male by the relative length of spines on the fifth pair of legs. This species has been recorded from scattered locations around the coast of New Zealand

New Zealand

New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

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External links

• Acartia jilletti at World of Copepods